The latest analysis of the battle for control of the U.S. House of Representatives conducted by the University of Virginia Center for Politics says Democrats are on the verge of having enough seats but aren’t quite there yet. The report says there is one congressional race in Florida that is causing Democrats “heartburn.” That’s the contest for the state’s District 27 seat to succeed current Rep. Ileana Ros-Lehtinen.

The Sabato Crystal Ball report compiled by political scientist Larry Sabato says barring a change in the political environment in favor of Republicans, Democrats stand to pick-up a bare minimum of seats ranging from the mid to high teens. They need to gain 23 seats in order to take control of the House.

The District 27 seat in South Florida was considered to be a good possibility for the Democrats to pick-up a Republican-controlled seat this year. After all, Hillary Clinton won the district by 20 points in 2016. But former University of Miami President and Health and Human Services Secretary Donna Shalala (D) is locked in a close battle with former journalist Maria Elvira Salazar (R).

The managing editor of the Crystal Ball, Kyle Kondick, has placed the District 27 contest as one of four races in the country that fall under the category of  “Democratic progress: Progressing but could fall short.”

The race is probably something close to a tie, with Salazar running a more spirited campaign than Shalala: Mason Dixon-Telemundo 51 had Salazar up 44%-42% in a recent poll. We’re keeping it at Leans Democratic for now, but if Democrats flub any of these four races, FL-27 is the one they would lose, and the uncertainty there is what could cause the Democrats to come up short in this category..

Another Florida congressional race where a Republican currently controls the seat is being categorized by the Crystal Ball as Democratic progress: On track with potential to overperform. That’s the Fl-26 seat currently held by Rep. Carlos Curbelo (R).

Just like FL-27, FL-26 appears to be very close: Mason Dixon-Telemundo 51 peggedCurbelo’s lead at just 46%-45% recently (Republicans believe Curbelo is in better shape; Democrats believe it’s tied). One could argue that both FL-26 and FL-27 should be Toss-ups; as it stands right now, and because we want to avoid excessive Toss-ups with Election Day approaching, we’re holding FL-27 as Leans Democratic and FL-26 as Leans Republican.

Curbelo is running against Democrat Debbie Mucarsel-Powell.

The Crystal Ball report concludes that when it comes to control of the U.S. House, Democrats are knocking at the door, but they are not quite there yet.

That works out to a Democratic gain of 19 seats, six short of the goal of 25 assuming that the Republicans pick up at least two current Democratic seats. And, remember, Republicans may pick up more than just two Democratic-held seats, although probably not many more than that. Another way of looking at this is that we see the floor for net Democratic gains as 17, about three-quarters of the way to 23 net seats, which would flip the House to a Democratic majority.

The report concludes that with less than weeks remaining before the election, there are 212 seats at least leaning to the Democrats, 201 at least leaning to the Republicans, and 22 Toss-ups. “Democrats need to win six of the Toss-ups to win the House, and all the other seats that currently lean to them (some of which are still very much in play), to win the House,” the report says.