They supply the data needed by political executive for formulating the policies and formulate several alternatives policies in respect of a particular sphere of government activity with its merits and demerits. 

The two-ballot or second-ballot system is another means of ensuring that the winning candidate is supported by a full majority of voters. Under this system, balloting may take place in two stages. During the first, voters have a choice among several candidates, only one of whom they may vote for. If no clear winner emerges from this first round of voting, a second ballot is held between the two candidates with the best showing. 

a. USA - The States.
b. India - Union Parliament 

The differences: 
Political:
i. It consists of the executive head of the state and other heads of the executive departments is ministers. Ministers are political leaders. They are mostly elected representative of the people and responsible for all their decisions and policies before the public. Political Executive work for a fixed tenure of about 5 years.

ii. It acts as a temporary executive in the sense that it changes after every election. After completing one tenure, ministers have to again contest elections. They can again become ministers only when the party to which they belong returns to power as the majority party.

iii. The ministers are amateurs, non-experts and non-professionals. Their function is to formulate policies and get these policies and laws approved from the Legislature. Thereafter these policies and laws of the State are implemented by the civil servants, who work under the control of Political Executive. The political executive heads the government. Each minister is head of a department or some of the government.

Permanent:
i. It consists of the civil servants (Bureaucracy) from the lowest to the highest levels. It carries out the day to day administration by working in the government departments. The civil servants are politically neutral. They do not owe allegiance to any political party.

ii. Their job is to carry out the laws and policies of the government without any political consideration. They are specially educated and trained persons. They are experts and professionals. They give expert advice and opinion as well as collect, classify and present data to the political executive on the basis of which the latter takes all decisions.

iii. Once appointed, the civil servants remain in office till the attainment of the retirement age, usually up to the age of 55 or 60 years. They get regular and fixed salaries and are hierarchically organised into higher and lower relationships.