Sinema left the Democratic party. Democratic donors left her too.

Democratic donors have fled Sen. Kyrsten Sinema since she left the party — and she hasn’t made up the loss with Republicans or independents.

That dynamic encapsulates the challenge the Arizona independent faces as she weighs whether to seek reelection: Sinema quit a party with which she was often at odds, and now she will have to build a base using only her personal brand.

The campaign finance data indicate it will be a daunting task.

A POLITICO analysis of her donors in recent cycles reveals her previous contributors are more loyal...