Not really. Democrats had a huge cash advantage in 2020.
Democratic candidates and groups have spent $6.9 billion, compared to $3.8 billion for Republicans. Democrats' spending falls to $5.5 billion when excluding spending by billionaire presidential candidates Michael Bloomberg and Tom Steyer.https://www.opensecrets.org/news/2020/10/cost-of-2020-election-14billion-update/
Studying exit polls, one sees a lot of ticket splitters, especially independents voting for Biden, then Republican down ballot. A good example of this is 41% of independents voting for Republican for Trump, 48% of independents voted for Republican congressional candidates, 51% of independents voted for Republican senate candidates, 54% for Republican governor candidates.
Defund the police didn't stick to Biden, maybe some of it did, but the independents dislike of Trump was more than enough to overcome that slogan. But apparently, the dislike of Trump didn't reach much below Biden.
An historical note here, Biden became only the second candidate to win the popular vote on his way to winning the presidency to lose seats in the house in this nation's history. The only other time was in 1884, Grover Cleveland who lost 18 house seats while winning the presidency and the popular vote 48.9 to 48.3%.
The thing is it wasn't money as the democrats had a huge advantage there. Just the presidency alone, Biden spent 1.6 billion to Trump's 1.1 billion rounding off. https://www.opensecrets.org/2020-presidential-race
I think the bottom line is Defund the Police was just a dumb slogan where independents took defund to mean defund as in Webster's definition. Not reform. Thus the huge difference in the percentage of vote for Trump 41% and congressional Republicans 48%. That's a lot of ticket splitters. 41.3 million independents voted in 2020, 16.9 million for Trump, but 19.8 million for Republican congressional candidates going by CNN exit poll percentages. Just independents alone had almost 3 million ticket splitters.https://www.cnn.com/election/2020/exit-polls/president/national-results