They didn't pass a resolutions by themselves, they passed a budget that only needed 50 votes. The last resolution was passed in September with the help of Democrats.

Republicans will need another continuing resolution or an appropriations bill in December to keep the government running. They will probably need Democratic votes again because a lot of Republican members vote no on CR/Appropriations bills since the bills don't cut spending to their liking.

When that happens Republicans don't have the votes to pass the CR/Appropriations bill by themselves and look to the Democratic minority for votes.