03:08 - Source: CNN
Bernie Sanders is rising in the polls. Here's why
CNN  — 

Joe Biden has earned the Democratic presidential endorsement of Iowa Rep. Cindy Axne, giving the former vice president a boost at a critical time – just nine days before the state’s caucuses.

Axne, a first term congresswoman, was one of two Iowa Democrats to flip a Republican held district in the state in 2018, and districts like hers could be critical in maintaining the Democratic majority in the House in November.

“I believe we need a Democratic nominee who not only has the vision to rebuild our alliances and strengthen our middle class, but who can win in November - which is why I’m proud to endorse Joe Biden for President,” Axne said in a statement. Axne will appear with Biden at his event in Ankeny, Iowa, Saturday evening, according to the Biden campaign’s Iowa spokeswoman, Julia Krieger.

Biden now has the support of two of Iowa’s three Democratic congressmembers. Rep. Abby Finkenauer of Iowa, who also turned a red district blue in the 2018 midterm elections, announced her endorsement of the former vice president earlier this month. Rep. Dave Loebsack, the third Democratic member of Iowa’s congressional delegation, is backing former South Bend, Indiana, Mayor Pete Buttigieg.

Biden also has the support of former Iowa Governors Chet Culver and Tom Vilsack.

Ahead of the caucuses, Biden has leaned heavily into arguing that having his name at the top of the ticket would help Democrats in down ballot races.

“I’m just asking the rhetorical question – Bernie’s at the top of the ticket in North and South Carolina, or Warren’s the top of the ticket. How many Democrats down the line you think are gonna win?” Biden told The State newspaper this week.

To support this argument, Biden’s campaign has rolled out several endorsements from swing district members across the country.

This weekend three Democrats who turned red districts blue – Finkenauer, Rep. Chrissy Houlahan of Pennsylvania, and Rep. Colin Allred of Texas, are traveling through Iowa on a “We Know Joe” tour. Rep. Conor Lamb of Pennsylvania, who also won a Republican district in a 2018 special election, campaigned with the former vice president in the state earlier this week.

The former vice president is set to return to Iowa on Saturday as he prepares for the final stretch of campaigning before Iowans caucus on February 3.

The race in Iowa remains fluid as Biden is joined by Buttigieg and Sens. Bernie Sanders of Vermont and Elizabeth Warren of Massachusetts in the top tier of contenders. And, a CNN poll conducted by SSRS released this week showed Sanders improving his standing in the race, joining Biden in a two-person top tier above the rest of the field.

A majority of Democratic caucusgoers have not firmly made up their minds about who they will support on caucus night.