Mayor Pete Buttigieg has jumped to third in Iowa, according to a poll of the state released on Monday.

The Suffolk University/USA TODAY poll shows that Vice President Joe Biden and Sen. Elizabeth Warren are battling for the lead with Biden at 18 percent and Warren at 17 percent.

The South Bend mayor tangled with Sen. Elizabeth Warren in the last Democrat presidential primary debate, suggesting some of her policies were too radical, especially her proposal to end private health insurance in favor of Medicare for all.

Buttigieg is at 13 percent, up seven points from the poll taken in June.

Former Vice President Joe Biden lost five points in support since June and Sen. Kamala Harris plummeted 13 points in the same time period.

The poll surveyed 500 likely Democrat caucusesgoers in Iowa.

But voters appear to be growing more uncertain as the Democrat primary contest continues.

The number of undecided caucus goers has jumped eight points since June — now at 29 percent.