The unlikely win of a US Senate seat by a Democratic candidate in deeply Republican Alabama has underscored the power of black voters—and the terrible job Democrats have done of courting them in the past.

Doug Jones, the former federal prosecutor who beat Roy Moore in the Alabama special election, launched an unusually aggressive campaign reaching out to African-Americans in the state. If Democrats want to recreate his victory elsewhere, they’re going to have to inject the same kind of resources—and then some. Other Republican candidates are unlikely to motivate black Democratic voters to go to the polls in opposition more than Moore, who had waxed nostalgic about the days of slavery.

Black leaders have been urging the Democratic party to do more to motivate voters in their community for a while. They say Democratic candidates have taken black voters for granted and don’t speak about the issues they care most about. They’ve put little effort into convincing African-Americans to vote, and when they do, it’s at the very last minute. Ahead of the Alabama election, a writer for African-American culture magazine The Root condemned the “entire Democratic party,” including Jones, as “trash” in a piece that listed those and other grievances.

Now that the Alabama results have Democrats finally paying attention, African-American voters, activists and their advocates are reminding the party of those failures, and offering advice on how to make up for them. The Brookings Institution has compiled a list of 26 cities with a majority African-American population that could help Democrats win or hold Senate seats in 2018. These would be good places for Democrats to start:

City Total population % of Black population 18+ Wilmington, Delaware 71,549 41 Lauderhill, Florida 69,979 59 Miami Gardens, Florida 112,021 58 North Miami, Florida 62,042 46 Pine Hills, Florida 66,906 51 Gary, Indiana 78,483 62 Baltimore, Maryland 622,454 49 Bowie, Maryland 56,885 38 Waldorf, Maryland 71,399 41 Detroit, Michigan 690,074 62 Flint, Michigan 99,802 41 Pontiac, Michigan 59,928 38 Southfield, Michigan 72,859 56 Jackson, Mississippi 173,212 59 Camden, New Jersey 76,904 34 East Orange, New Jersey 64,578 71 Irvington township, Essex County, New Jersey 54,320 63 Newark, New Jersey 279,793 38 Trenton, New Jersey 84,632 38 Mount Vernon, New York 68,221 52 Cleveland, Ohio 390,584 39 Memphis, Tennessee 657,167 47 DeSoto, Texas 51,478 54 Hampton, Virginia 137,081 39 Portsmouth, Virginia 96,135 40 Richmond, Virginia 213,735 39

And 31 cities that could make a difference in 2020 for the Senate—and for the presidential race by default.

City Total population % of Black population 18+ Birmingham, Alabama 212,211 56 Mobile, Alabama 194,669 38 Montgomery, Alabama 202,967 44 Wilmington, Delaware 71,549 41 Albany, Georgia 76,466 52 Atlanta, Georgia 448,901 42 Augusta-Richmond County, Georgia 196,635 41 Macon-Bibb County, Georgia 154,608 39 Savannah, Georgia 142,919 41 Valdosta, Georgia 56,504 38 Baton Rouge, Louisiana 229,186 42 Lake Charles, Louisiana 74,190 35 New Orleans, Louisiana 376,738 46 Shreveport, Louisiana 200,015 41 Detroit, Michigan 690,074 62 Flint, Michigan 99,802 41 Pontiac, Michigan 59,928 38 Southfield, Michigan 72,859 56 Jackson, Mississippi 173,212 59 Camden, New Jersey 76,904 34 East Orange, New Jersey 64,578 71 Irvington township, Essex County, New Jersey 54,320 63 Newark, New Jersey 279,793 38 Trenton, New Jersey 84,632 38 Rocky Mount, North Carolina 56,642 48 North Charleston, South Carolina 104,146 36 Memphis, Tennessee 657,167 47 DeSoto, Texas 51,478 54 Hampton, Virginia 137,081 39 Portsmouth, Virginia 96,135 40 Richmond, Virginia 213,735 39

Some of the cities on the lists are in toss-up states where a sliver of the electorate has the potential to swing the results, such as Michigan and Florida.

They also include places in Republican strongholds such as Texas, Mississippi, and South Carolina that went for Donald Trump by a wide margin in 2016. In the past, Democrats had written off those states as unwinnable. Alabama might change those calculations.

“When society’s assumptions around who should be valued catches up to the actual assets in black communities, we will see the kind of victories in Alabama in all of our communities, businesses and schools,” wrote Andre Perry, a fellow at Brookings metropolitan policy program.