A spate of polls in a trio of suburban House seats come with bad news for Donald Trump and his chances at winning reelection in November.

Internal polls from Democratic candidates have Trump losing to Democratic nominee Joe Biden in three seats Trump carried in 2016, showing his standing with suburban voters is sliding and threatening to sink his bid.

"I'm confident in Biden's current advantage because we're seeing it on so many levels," Nathan Gonzales, a nonpartisan political handicapper with Inside Elections, said in an interview with the American Independent Foundation. "Compared to 2016, Trump is underperforming at the national, state, and House district level. It's all pieces of the same puzzle."

First, a poll for the Democratic nominee in Texas' 3rd District — a suburban Dallas seat which Donald Trump won by 14 points in 2016 — showed Biden leading by 3 points. If that poll holds, it would amount to a 17-point swing in just four years.

"When you look at how poorly Trump is performing in the competitive House districts in Texas, it makes sense that the race is close statewide," Gonzales said.

Another Democratic internal poll in Nebraska's 2nd District showed Biden up 6 points. If that polling holds, it would be another big swing from the 2 points Trump carried the district by in 2016.

A loss in Nebraska's 2nd District has even bigger ramifications for Trump, thanks to the way the Cornhusker State awards its Electoral College votes. The statewide winner gets two Electoral College electors, while the state's three other Electoral College votes are given out based on which candidate wins each of the state's three House seats. If Biden wins Nebraska's 2nd District, he'd pick up another Electoral College vote that Trump cannot afford to lose.

And a third internal poll in Missouri's 2nd District — located in the St. Louis suburbs — also showed Trump down 3 points to Biden. Trump carried that seat by 10 points in 2016; a poll showing him losing there is yet another signal he's hemorrhaging support.

Of course, internal polls for candidates should be taken with a grain of salt.

But CNN polling expert Harry Enten wrote earlier this year that "when one party puts out a lot more internal polls than normal, it is good for their side." And this cycle, Enten reported that Democrats have been releasing far more internal polling than Republicans.

Trump, for his part, has tried to appeal to suburban voters with racism, looking to scare suburban women into believing that minorities will "invade" their towns.

Experts say the polls show signs that Trump's messaging is not working — which could spell doom for him come Nov. 3.

"College-educated white women are the key swing group," Stu Rothenberg, a nonpartisan political handicapper and columnist at the congressional newspaper Roll Call, said in an interview with the American Independent Foundation. "They were dramatically more Democratic in 2018 than they had been in 2016, and all the evidence is they are going to be even more dramatically Democratic in 2020. And it's a problem for Donald Trump."

Published with permission of The American Independent Foundation.