Pete Buttigieg has surged into third place in the key state of Iowa, according to polling.

The out South Bend mayor is proving surprisingly popular in the traditionally-conservative state, surpassing Bernie Sanders to make it into third place.

Pete Buttigieg is third in Iowa, ahead of Bernie Sanders.

According to the Suffolk University/USA Today poll, 13 percent of Iowans support Buttigieg, behind only Elizabeth Warren on 17 percent and Joe Biden on 18 percent in the crowded Democratic field.

Sanders, who has seen his left-wing support eroded by Warren, is in fourth on 9 percent, with no other candidate receiving above 3 percent in the poll.

The Iowa caucuses, set to take place on February 3, are traditionally the first event of the presidential primaries – marking the state as a key battleground for candidates hoping to show they have momentum.

Other polls over the past month have generally placed Buttigieg in fourth nationally, behind Biden, Warren and Sanders, just ahead of senator Kamala Harris and well clear of the remaining 2020 Democrats.

Buttigieg has unveiled a bold plan for LGBT+ rights.

Buttigieg recently revealed his ambitious LGBT+ policy platform, including pledges to update US passports to recognise non-binary people, ensure access to PrEP for everyone who needs it, and provide LGBTQ+ inclusive lessons and health education.

He said: “I will press for and sign the Equality Act into law as soon as it hits my desk, making anti-discrimination the law of the land.

“I will deliver quality health care that is affordable, accessible, and equitable for all Americans, regardless of their sexual orientation, gender identity, or race.

“My administration will put us on a path to end the HIV/AIDS epidemic—which disproportionately affects gay men and transgender women of color —by 2030, and ban the dangerous practice known as ‘conversion therapy’ once and for all.

“I will use more comprehensive strategies to end hate-based violence against LGBTQ+ people, especially black transgender women; increase access to housing for LGBTQ+ Americans; and strengthen protections for LGBTQ+ immigrants and refugees.”

Buttigieg also pledged to “conduct a thorough examination of unconstitutional religious exemption policies in the federal government, especially those deployed by the Trump administration to undermine the rights of LGBTQ+ people”.