Yes, you can.
H1 is being owned by the Employer independent to another employer sponsoring his/her own H1B for the same candidate(except for annual cap filings each year lottery).
Thus, these two employer’s petitions are independent, parallel and mutually exclusive for you being the candidate(only corner case is if there is any fake or criminal issue on your records).
Thus, any of the above employer’s petition can be approved at any time. Once an approval comes in, you work for them(getting paid by that employer), the other approvals, even before or later, would go into the drain.
Imagine, you have applied for few jobs and got 4 offers, you can take any offer from any employer at any time and continue to work for that employer. like that.