Former Pennsylvania Senator Rick Santorum is ending his 2016 presidential bid, CNN reports. Santorum, who edged eventual nominee Mitt Romney in the 2012 Iowa caucus, was unable to gain any momentum in this year's campaign. He finished a distant 11th, with just 1%, in the 2016 caucus held earlier this week.

Santorum is the second candidate to exit the race today; Rand Paul announced his departure this morning. Mike Huckabee and Democrat Martin O'Malley have also left the race since Monday.

Nine Republicans remain: Cruz, Trump, Rubio, Carson, Bush, Fiorina, Kasich, Christie & Gilmore. 

Kentucky Senator Rand Paul became the third person to end a 2016 presidential campaign on the heels of a poorer than hoped-for showing at the Iowa caucus. Paul announced he was suspending his campaign:

“Although, today I will suspend my campaign for president, the fight is far from over,” Mr. Paul said in a statement. “I will continue to carry the torch for Liberty in the United States Senate and I look forward to earning the privilege to represent the people of Kentucky for another term.”

Updating an earlier story, Hillary Clinton has been declared the winner of the Iowa caucuses based on the final results of the Democratic Party there. The Party indicated it would not be doing a recount despite the close result. A spokesman for the Sanders campaign indicated that it wouldn't challenge the results.

Clinton won by about 0.3%. She earned 23 delegates, Sanders 21. Eight delegates remain unallocated at this time. 2,383 delegates are needed to win the nomination.

Despite the Clinton campaign's victory claim, the Iowa Democratic caucuses remain too close to call, according to a late morning update to clients from The Associated Press. 

With all but one precinct reporting, Clinton has just a three-tenths of one percent (0.3%) lead over Sanders. The update goes on to note that Sanders hasn't conceded and the state Democratic Party has not commented on whether a recount is forthcoming.

Republican: Ted Cruz won the Iowa caucuses, with about 28% of the vote. In a close three-way race, Donald Trump and Marco Rubio were next at 24% and 23%, respectively. Cruz and Rubio outperformed the polling average by several points, while Trump underperformed slightly. 

Delegates are allocated proportionately in Iowa so delegates were pretty evenly split among the top three finishers. Cruz received 8, with Trump and Rubio getting 7 each. A few delegates remain unallocated at this point.

Mike Huckabee received about 2% of the vote, and suspended his campaign.

Democrats: Hillary Clinton and Bernie Sanders both received about half the vote in an exceptionally tight race. Clinton's campaign has claimed victory, but the race has not been called by the Associated Press as of this writing. Regardless of who ultimately wins, the delegate account is proportional here as well so it doesn't make much practical difference, beyond bragging rights. The exact delegate numbers are a little sketchy, but it looks like Sanders will have 21, with Clinton having between 23 and 29, depending on whether so-called 'super delegates' are included. Click or tap the above graphic to see the full Democratic results.

Martin O'Malley received less than 1% and also withdrew from the race.

Up next: New Hampshire primary on February 9. Trump has a huge lead in Republican polling, with Sanders also well ahead in the Democratic polls.

Ted Cruz has won the Iowa Republican caucus, edging Donald Trump and Marco Rubio.  Former Arkansas governor Mike Huckabee has suspended his campaign.

After a poor showing in Iowa, former Maryland governor Martin O'Malley is expected to suspend his campaign.

This will leave a two-person Democratic race. As of this writing, Iowa is too close to call between Sanders and Clinton.

We've added delegate state maps to our Republican and Democratic nomination pages. These maps let you see how many delegates each state will send to the respective party's national convention. You can choose to view the map based on time, contest type or allocation method, and from there look at any slice of those three elements.

Each state can be clicked or tapped to get a little more detail on the state's contest as well as a polling average (if enough recent polls are available) and individual poll detail.

This Republican map, for example, is based on allocation methods, and shows how the 689 delegates up on Super Tuesday will be allocated.

Within the time dimension, there's also an option for 'Up Next', which will highlight the next date one or more contests are being held. It's not particularly exciting with only one, but here's the Democratic map using that filter:

The polling is (should be) done, and the vote takes place tonight at the Iowa caucuses. 

Republicans: Donald Trump has led in all recent polls, averaging a four point margin over Ted Cruz in the last five polls. Rubio has been gaining some momentum in recent surveys, although the 'gold star' Iowa poll out over the weekend had him well back of Cruz and Trump. It wouldn't be terribly surprising if there was a very close 3-way battle tonight; perhaps with Trump, Cruz and Rubio finishing within 5% of each other.

Democrats: Polls have varied widely in this race, although many of the most recent ones have shown a slight lead for Hillary Clinton. It appears that turnout for the Sanders campaign will be crucial in determining whether the Vermont Senator can score an important early win. Either way, it is looking good for Sanders in next week's New Hampshire primary. A new poll out this AM has him up by 31 points over Clinton.

Third term Republican Reid Ribble (WI-08) announced his retirement over the weekend, turning a safe Republican district into a toss-up race for 2016.

37 House members have announced they are not running this year, 22 Republicans and 15 Democrats. Of those, eight Republican seats are highly competitive (toss-up or lean per Sabato's Crystal Ball). Four are competitive on the Democratic side.

Seven members of each party are leaving to run for the U.S. Senate; a single Democrat is running for governor with another running for local office. The remaining six Democrats and 15 Republicans are retiring (or have not announced plans to run for another public office).

The full list of departures, as of February 1, follows: