For both politicians campaigning, or politicians that are already elected, how are their staff paid? Does it from the the politician's pocket (which I am assuming is the case for someone that is campaigning but not elected) or say are they allotted money from their state to hire assistants/aides? what about a currently elected politician who is also campaigning for re-election?
There is a big red line between campaign staff and member's staff, at least when it comes to the U.S. Congress. Violating it can land you in jail. To wit:
Congressional staff (e.g. Congressional aides, etc. ) are paid from a budget set aside for the purpose. This budget, called the Members Representational Allowance covers costs for staff, mailings, and personal expenses. The Statement of Disbursements is a record of the allowances for each office, and is usually between $1.2 - $1.5 million per member. You can find your representative's office in this document.
The actual budget for each member varies, because it is based on actual expenses, but generally this is just a line item paid by the treasury from tax dollars. Trust me when I say staffers are not getting rich.
The House sets the funding levels for the MRA annually as part of the federal budget process. According to the CRS report, this amount decreased from a total of $660 million for fiscal year 2010, to $573.9 million for fiscal year 2012. In 2012, individual representatives received MRA allowances ranging from $1,270,129 to $1,564,613, with an average of $1,353,205.13.
Interesting note from an article in NV called "How much does it cost to run a congressional office":
In the House, lawmakers can’t hire more than 18 full-time employees — with a special allowance for an extra four part-timers, temps or paid interns. Additionally, none of those full-time employees can receive a salary of more than $168,411. Senators, meanwhile, don’t have such limits — though committee staffers can’t be paid more than $171,315.
The Congressional Management Foundation has guidance for freshmen on how to set up their offices.
Election staff is paid from the campaign fund, details of which must be reported to the Federal Election Commission on a quarterly basis, or it's local equivalent in the state. This fund may be funded by the member, the party, corporations, or individual contributors- but except for the member, there are strict limits on the amounts. Election staff that are paid (and there are usually only a few) are expenses no different than attack ads or junk mail.
While in the buildings, staff may not so anything related to the campaign. If they do, the member will definitely be talking to the ethics committee and could end up in jail. Interestingly, if you want to see what they are paid, you can go [here], since these payments are a matter of public record.
If the staff member wants to do something for the campaign, the Hatch Act allows the staff member to express their first amendment rights, but makes it very clear that it must be on their own time and done of their own free will with no compulsion from the member.
If the staff member wants to be more involved in the campaign (and this is not unusual) the staff member may take a unpaid leave of absence while the campaign is on. During this time, the party or the campaign fund may pay this person if they so choose.
The point in all of this,however, is that you are working for the campaign or for the members staff. It must be clear which and may not be both.
While it depends on how the campaign is financed, campaign staffers are usually divided into two groups: Paid employees and volunteers. The paid employees are usually the higher level staffers of the campaign (the campaign manager, public relations, consultants,etc). These people are often very expensive and they are compensated from the funds the candidate raises from campaign donations or in some cases from the candidate's own money that they invest into the campaign.
Lower level positions are almost always staffed by volunteers. They answer the phones, pass out fliers and literature, post signs,etc and perform the more basic tasks in the campaign. These are usually supporters of the politician who are drawn in from local functions or they are people who simply walk in off the street and volunteer their time. The number of volunteers almost always outnumbers the paid staff and they are often only "compensated" with free food and drink and the opportunity to claim that they worked on the campaign. In rare cases, they may be offered roles in the politician's administration; but those are exceptional instances.
In the United States, both state and federal funding is rather minimal and most campaigns are financed by private contributions. That is why politicians often spend as much time raising money for their campaigns as they do enacting legislation and addressing issues of concern to their constituents