New York, Nov 14 (AFP) Former Massachusetts governor Deval Patrick joined the crowded 2020 presidential race on Thursday, signalling the concern some Democrats have about the leading candidates just three months before the first primary.

The 11th-hour entry of Patrick, one of the first US African-American governors, reflects the unsettled nature of the Democratic contest and comes as billionaire businessman Michael Bloomberg also considers running.

Patrick, 63, announced his bid for the White House in a 2:35-minute video posted on his website, becoming the 18th candidate in the Democratic pack. Nine others have already dropped out.

"They bring a richness of ideas and experience and a depth of character that makes me proud to be a Democrat," Patrick, who is close to former President Barack Obama, said of the other candidates.

"But if the character of the candidates is an issue in every election, this time is about the character of the country," he added.

Patrick, who had said last year he wouldn't run, this week officially entered the race by filing paperwork to join the New Hampshire primary ballot.

His change of mind highlights anxieties among party centrists who fear that the left-wing policies of Elizabeth Warren and Bernie Sanders will damage the Democrats' chances of beating President Donald Trump next year.

The leading centrist in the race is former vice president Joe Biden, but he has struggled to maintain his frontrunner status and Democratic voters are far from uniting behind one candidate as the clock ticks down to party primaries early next year.

Moderate Pete Buttigieg has eaten into some of Biden's support. A poll of likely voters this week showed the mayor of South Bend, Indiana in the lead in Iowa, the first state to vote in the Democratic nominating process.

Experts say a Bloomberg candidacy could also hurt Biden. The former New York mayor has yet to officially declare that he is running for the White House but has taken formal steps to do so.

On Tuesday Bloomberg, who like Trump is a septuagenarian white New York billionaire, submitted paperwork to be on the ballot in Arkansas, four days after doing the same in Alabama.

It is unclear what sort of impact Patrick's entry might have, with some commentators suggesting he has waited too long. He also doesn't have the personal wealth that Bloomberg has to call upon.

Others suggested Patrick, who served two terms as governor of Massachusetts from January 2007 to January 2015, may do well in Democratic areas with primarily black voters.

Senator Kamala Harris of California and New Jersey Senator Cory Booker, two other African-American candidates in the race, are both languishing in the polls.

Patrick, born into a poor family in Chicago before receiving a scholarship for Harvard University, signaled that he planned to run as a moderate and hoped to distinguish himself with hopeful rhetoric.

He told CBS news that he did not support Medicare for All, a comprehensive state health plan backed by Warren and Sanders. He said it must be an opt-in service and not obligatory for everyone.

Patrick, a lawyer with a track record in civil rights advocacy who also worked for oil giant Texaco, said taxes should be raised for the most prosperous but "not as a penalty."

Biden leads the national polls at 26 percent, ahead of Warren at 20 percent and Sanders 17 percent, according to realclearpolitics.com. (AFP)

(This is an unedited and auto-generated story from Syndicated News feed, LatestLY Staff may not have modified or edited the content body)